• Proceedings of the KIPE Conference
• /
• 2020.08a
• /
• pp.399-400
• /
• 2020

본 논문은 Sensored BLDC 모터의 제어방법을 설명하고, 효율적인 최적 제어를 하기위해 Lead Angle 제어를 하는 방법에 대하여 설명하였다. Lead Angle 값을 실시간 Auto Tuning 하는 기법을 설계 및 구현하였다. 실제 Microchip 사의 DSC를 사용하여 Software로 동작을 구현하였으며, PWM 스위칭 하기 위한 반도체 소자는 IGBT 모듈인 IPM을 사용하여 BLDC 모터의 구동회로인 인버터를 구성하였다. 실제 사용하는 400W급 BLDC 모터를 사용하여 Lead Angle 제어와 Auto Tuning 실험결과를 비교 검증하였다.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.24 no.5
• /
• pp.129-135
• /
• 2010

It is well known that distributed generation(DG) system using renewable energy is an alternative to solve the problems which result from the exhaustion of fossil fuel and the environmental pollution. A PWM inverter is required for a power flow control in the DG systems. This paper proposes a SRF power flow control method considering grid impedance in grid-connected single-phase inverter systems. The proposed SRF power flow control method can provide a voltage-reference for the single-phase inverter even without any grid impedance estimation so that the single-phase inverter system could operate in stand-alone mode and grid-connected mode based on the known nominal value of grid impedance. Also independent controls of active and reactive power are achieved by the proposed control method. The effectiveness and the validity of the proposed control method are demonstrated through simulations. The simulation results show that the proposed control method can control properly power flow in grid-connected single-phase inverter systems.

• Journal of the Institute of Convergence Signal Processing
• /
• v.8 no.2
• /
• pp.113-118
• /
• 2007

In this paper, a novel approach to using Subcircuit of Pspice in designing feedback for DC-DC converter systems is proposed. Proposed new approach, the feedback design procedures which are based on small signal modeling are programmed as a subcircuit in Pspice. For this purpose, Analog Behavioral Modeling (ABM) is used. By using the subcircuit, the component values of the error compensation amplifier can be easily obtained by means of Pspice DC analysis. The methodology of development is presented in detail and application examples demonstrated the effectiveness of the proposed approach in designing feedbacks for DC-DC converters. The converter with PWM method used continuous current mode and calculated buck converter control signal with average and linear current technique. To decide pole and zero K-method was adapted and this kind of design procedure took stable function.

• Journal of the Institute of Electronics Engineers of Korea SC
• /
• v.48 no.1
• /
• pp.31-38
• /
• 2011

Faults of motor drive systems to be used for various industrial applications can cause serious problems. In this paper, a method to diagnose switch open fault of a voltage-fed PWM inverter is proposed. The proposed method normalizes dq current and fault-detection and first classification are performed by mean values of dq phase currents, second classification is performed by features such as the relation of dq phase currents, the ranges of those, the positions of those according to the results, and fault switch is diagnosed with the results. The proposed method performs the simulation for diagnosis of inverter switch open faults with MATLAB and identifies the feasibility of the proposed method. Because the proposed method is implemented by simple algorithms, the proposed algorithm can be embedded in general induction motor drive systems and be used.

• Proceedings of the KIEE Conference
• /
• 2002.04a
• /
• pp.9-11
• /
• 2002

본 논문에서는 고속 회전기의 자기 베어링을 위한 새로운 파인 앰프(Power Amplifier) 구성 방법에 대하여 논하고자 한다. 그리고 이를 위한 새로운 PWM 구현 방법을 제안한다. 제안된 방법은 6개의 IGBT로 구성된 3개의 암(Arm)을 내장한 파워 모듈(Power Module)을 이용한다. 제안된 방법을 통해 필요한 파워 모듈의 숫자를 줄이면서도 자기 베어링 코일에 효과적으로 전압을 인가할 수 있음을 보인다. 또한 자기 베어링 1자유도 모의 실험 장치를 구성하여 제안된 방법의 실효성을 검증한다.

• Proceedings of the KIEE Conference
• /
• 2009.04b
• /
• pp.143-145
• /
• 2009

본 논문에서는 AC-AC 직접 변환 방식인 매트릭스 컨버터의 진압 변조 방법 중 하나인 $V_{max}-V_{mid}$ PWM 변조 방법을 간략화한 Simple $V_{max}-V_{mid}$ 전압 변조 방법에 대해 소개한다. $V_{max}-V_{mid}$ 전압 변조 방법은 실행 전에 입력전압 위상각$(\theta_E)$을 판별하는 PLL(Phase Looked Loop)과정을 거친 후, 얻은 위상 정보를 사용하석 게이트 신호를 만들어 낸다. 하지만 PLL의 사용이 연산 시간의 딜레이를 발생시키고, 처리과정을 복잡하게 만드는 단점으로, PLL과정을 생략하여 입력 전압의 크기 정보만으로 섹터를 판별하고 게이트 신호를 발생시켜 스위치를 조작하는 변조 방범을 사용하였다. 이로 인해 연산시간의 단축과 처리 과정의 축소 등의 이점을 취하고, 이를 시뮬레이션으로 검증한다.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.8 no.5
• /
• pp.1050-1057
• /
• 2004

The purpose of study is development of a fuzzy controller which independent of a computer and its software for fuzzy control of servo system. This paper describes a method of approximate reasoning for fuzzy control of servo system, based on decomposition of $\alpha$-level fuzzy sets, It is propose that fuzzy logic algorithm is a body from fuzzy inference to defuzzificaion in cases where the output variable u directly is generated PWM. The effectiveness of quantified $\alpha$-levels on input/output characteristics of fuzzy controller and output response of DC servo system is investigated. It is concluded that $\alpha$-cut 4 levels give a sufficient result for fuzzy control performance of DC servo system. The experimental results shows that the proposed hardware method is effective for practical applications of DC servo system.

• Journal of the Institute of Electronics Engineers of Korea CI
• /
• v.47 no.4
• /
• pp.102-108
• /
• 2010

The photovoltaic system changes solar energy into DC by solar cell and this DC is inverted into AC which is used in general houses by inverter. Recently, the use of power of the photovoltaic system is increased. Therefore, the study of 3 phase solar system to transmit large power is very important. This paper proposes a method that finds simply faults and diagnoses the switch open faults of 3-phase pulse width modulation (PWM) inverter of grid-connected photovoltaic system. The proposed method in $\alpha\beta$ plane uses the patterns of trajectory image as the characteristic parameters and differenciates a normal state and open states of switches. Then, the result is made into tree. The tree is composed of 21 fault patterns and the parameters to classify faults are a shape, a trajectory area, a distributed angle, and a typical vector angle. The result shows that the proposed method diagnosed fault diagnoses, classified correctly them, and made a pattern tree by fault patterns.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.17 no.2
• /
• pp.73-80
• /
• 2003

This Paper Proposes instantaneous following control method to control pulse modulation switching converter by using principle that reset time of integrator is inverse proportion in size of integrator input voltage. proposed control method acts of fixed frequency and control switch calculates time of become turn on and turn off using analog integrator. Duty ratio that express switching time of converter is depended on mean value of switching variable and following time consists in one cycle. Follow to do order exactly stationary state as well as transition state, and controller corrects mean value of control variable and control reference value and control as control error gets into zero. Proposed control method could experimented and know that experiment result and theory are agreeing well through this using the buck converter.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.15 no.3
• /
• pp.235-243
• /
• 2010

This paper describes a design method of LCL filter for grid-connected three-phase PWM inverter. First, by analyzing the ripple component of phase voltages and currents according to the PWM pattern of grid-connected three-phase inverter, the RMS value of the current ripple can be calculated. Then based on the analysis, the current THD in the inverter-side can be defined. After that by analyzing the dependency between the current THD of the system and the current ripple attenuation, the parameter of LCL filter can be designed. Finally, the described LCL filter design method is verified by showing a good agreement between the target current $THD_g$ and the actual one through the simulation and experiment.